Skinned Knee - Check In

Place the events of what happened to the skinned knee in order from beginning to end.

• Scab falls off, revealing a dark red dent in the skin underneath

• Skin becomes white and flakey, scab falls off to reveal no dent

• The scrape is no longer visible

• Skin is red, and a smaller scab forms on top

• The knee is scraped and has a large dark scab

Recall: We know that the blood plays a role in helping wounds to heal.

The blood does NOT fully heal the skin on its own, but what role DO the platelets in the blood play in the repair process?

• They form a clot to stop bleeding and create a base for new tissue to grow.

• They replace damaged skin cells directly with new cells.

• They fight infection by attacking bacteria at the wound site.

• They cool down the wound area to reduce inflammation.

Based on our observations, from which direction does the skin repair itself?

• From below

  New skin forms at the bottom and pushes up

• From Above

  New skin forms at the edges of the cut and grows down into gap

• From the Sides

  New skin forms along the walls of the cut and grows to the center

• Randomly

  New skin forms in patches all across the scrape

To repair the damage caused by the scrape, the knee skin will need to produce new skin . . .

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What do skin cells look like under the microscope?

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In our microscopic skin diagram we had several items. Please label what each part of the image represents

c

d

e

The gap caused by the skin injury

The layer of non-living cells in skin

The layer of dust flakes on skin

The layer of organized cells in skin

The fluid filling the skin injury

The blood filling the skin injury

The layer of living cells in skin

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What is the most reasonable hypothesis we can draw from the skinned knee video?

• To repair itself the skin needs to completely fill the gap caused by the scrape with new cells.

• To repair itself the skin only needs to cover the opening of the scrape with new cells.

• To repair itself the skin needs to coat the edges of the scrape with new cells

• To repair itself the skin only needs to produce a scab to fill the gap caused by the scrape.

Which part of the modern cell theory helps us better understand how the skin repairs itself?

• All living things are made of 1 or more cells

• Cells are the basic unit of all parts of the body

• All cells come from other cells that already exist

• Genetic information (DNA) is passed from one cell to the next

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What is one thing that we observed about the living cells under the microscope?

• Cells did not move or change much

• Cells increased in number and the skin increased in size

• White dots appeared in the cells and then popped apart

• Cells were active and moved around

What is one thing that you are wondering about the cells after observing the living cells under the microscope?

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